Roadway intersections, when warranted, require signalization to maintain safety and efficient movement of vehicular traffic. Traffic control devices (signals, signs, cameras, etc.) are generally supported on roadside posts, suspended from span wires or rigidly mounted on steel mast arms cantilevered over the roadway from a vertical pole that is designed as a rigid structure.
Steel mast arm traffic signal support structures are typically rigidly designed to resist high wind loads imparted to the poles and mast arms. The current design concerns (moments) are only directed now to the base of the pole and to the connection of the mast arm to the pole. In addition, the current designs use a rigid connection including drilled and tapped cast aluminum connections to connect the traffic signal to the mast arm. Common prior art cable securements rely on single in-plane surface plate to cable pressures and non-consistent, unpredictable use of acute cable angles.
What is needed in the art is an attachment device and an attachment assembly for connecting a traffic control device to a mast arm that provides a flexible connection for connecting the traffic control device to the mast arm. In some aspects, using cables to secure the traffic control device to the mast arm, an assembly including multiplane surface-cable pressures and that provides for consistent use of acute cable angles is needed.